ttrpg-tools/src/components/md-pin.tsx

import { customElement, noShadowDOM } from "solid-element";
import { createSignal, onMount, onCleanup, Show } from "solid-js";

customElement("md-pin", { x: 0, y: 0 }, (props, { element }) => {
  noShadowDOM();

  const [position, setPosition] = createSignal<{ top: string; left: string }>({ top: "0", left: "0" });
  const [visible, setVisible] = createSignal(false);
  const [transformStyle, setTransformStyle] = createSignal<string>("");
  let pinContainer: HTMLSpanElement | undefined;
  let targetImage: HTMLImageElement | undefined;
  let resizeObserver: ResizeObserver | undefined;

  // 从 element 的 textContent 获取 pin 标签内容
  const label = element?.textContent?.trim() || "";

  // 隐藏原始文本内容
  if (element) {
    element.textContent = "";
  }

  // 查找上方最近的图片
  const findNearestImage = (): HTMLImageElement | null => {
    if (!element) return null;
    
    // 从当前元素向上查找
    let current: Element | null = element;
    while (current) {
      // 在当前元素的之前兄弟节点中查找图片
      let sibling: Element | null = current.previousElementSibling;
      while (sibling) {
        // 检查是否是图片元素
        const img = sibling.querySelector('img');
        if (img) return img;
        
        // 检查元素本身是否有图片相关的类或标签
        if (sibling.tagName === 'IMG') return sibling as HTMLImageElement;
        
        sibling = sibling.previousElementSibling;
      }
      current = current.parentElement;
    }
    
    return null;
  };

  // 更新 pin 位置和容器样式
  const updatePosition = () => {
    if (!targetImage || !pinContainer) return;

    const imgRect = targetImage.getBoundingClientRect();
    const containerRect = pinContainer.parentElement.getBoundingClientRect();

    // 计算图片左上角相对于容器原始位置的偏移
    const offsetX = imgRect.left - containerRect.left;
    const offsetY = imgRect.top - containerRect.top;

    // 使用 transform 将容器移动到图片位置
    setTransformStyle(`translate(${offsetX}px, ${offsetY}px)`);

    // 计算 pin 在图片内的相对位置（x/y 是百分比）
    const x = typeof props.x === 'number' ? props.x : parseFloat(props.x) || 0;
    const y = typeof props.y === 'number' ? props.y : parseFloat(props.y) || 0;

    const left = (x / 100) * imgRect.width;
    const top = (y / 100) * imgRect.height;

    setPosition({
      left: `${left}px`,
      top: `${top}px`
    });
  };

  onMount(() => {
    // 查找目标图片
    targetImage = findNearestImage();

    if (targetImage) {
      // 初始定位
      updatePosition();

      // 使用 ResizeObserver 监听图片大小变化
      resizeObserver = new ResizeObserver(() => {
        updatePosition();
      });
      resizeObserver.observe(targetImage);

      // 延迟显示以等待位置计算完成
      requestAnimationFrame(() => {
        setVisible(true);
      });
    } else {
      console.warn('md-pin: 未找到目标图片');
    }
  });

  onCleanup(() => {
    if (resizeObserver && targetImage) {
      resizeObserver.unobserve(targetImage);
    }
  });

  return (
    <div
      ref={pinContainer}
      class="md-pin-container"
      style={{ transform: transformStyle(), 'transform-origin': 'top left' }}
    >
      <Show when={visible() && targetImage}>
        <span
          class="md-pin absolute transform -translate-x-1/2 -translate-y-1/2 pointer-events-auto
                 bg-red-500 text-white text-xs font-bold rounded-full w-6 h-6
                 flex items-center justify-center shadow-lg
                 z-10"
          style={{
            left: position().left,
            top: position().top
          }}
        >
          {label || '📍'}
        </span>
      </Show>
    </div>
  );
});